When speaking about PM2.5, the harmful particles found in smog, Ma said: 'The greater the particle diameter, the poorer the visibility.'

On January 3, a time lapse video emerged showing smog smothering the Chinese capital, completely changing the skyline in just 20 minutes.

Thousands of primary schools have suspended classes across the region.

China's Ministry of Environmental Protection announced on January 2 that it had punished 500 enterprises and construction sites for continuing to operate despite demands to close.

Photos taken on January 4 show the full extent of the air pollution.

Many people have taken to social media site Weibo to complain about the pollution.

One user wrote: 'I would rather have a slowdown in economy than heavy pollution.'

While another commented: 'the smog is so horrible...maybe we should have Chinese new year holidays earlier.'

And one user said: 'I haven't seen the nearby buildings for days now.'

Air pollution in China increases during the winter months with last November proving to be a particularly troublesome time for northern regions. Red alerts were issued in Jiangxi and Shanxi provinces during that time.